Acute Cytomegalovirus Research Articles

Childhood Langerhans cell histiocytosis hematological involvement: severity associated with BRAFV600E loads

Hematological involvement (HI) is one of the life-threatening risk organs (ROs) in Langerhans cell histiocytosis (LCH). Lahey criteria have defined HI since 1975 as hemoglobin <10 g/dL and/or platelets <100 G/L and/or leukopenia (white blood cell count <4 G/L) and/or neutrophils <1.5 G/. Among the 2313 patients <18 years old enrolled in the French National Histiocytosis Registry (1983-2023), 331 developed HI (median age at diagnosis: 1 year); median follow-up lasted 8.1 years. Bone-marrow aspirate smears and biopsies may show reactive histiocytes, hemophagocytosis or myelofibrosis but never confirm the diagnosis. Fifty-eight (17%) patients developed macrophage-activation syndrome, sometimes related to acute Epstein-Barr virus or cytomegalovirus infection, sometimes months before typical LCH manifestations appeared. Hemoglobin and platelet thresholds for initiating transfusion(s) appear to accurately distinguish 2 groups: mild HI (MHI; >7 g/dL and >20 G/L, respectively) and severe HI (SHI; ≤7 g/dL and ≤20 G/L). Each entity has different organ involvements, laboratory parameters, mutational status, blood BRAFV600E loads, drug sensitivities and outcomes (respective MHI and SHI 10-year survival rates: 98% and 73%). Since 1998, mortality first declined with combination Cladribine-cytarabine therapy, and then with mitogen-activated protein-kinase inhibitors since 2014. Forty-one (12%) patients developed neurodegenerative complications that have emerged as a risk for long-term survivors. These results suggest limiting the HI-RO definition to SHI, as it encompasses almost all medical complications of LCH. Future clinical trials might demonstrate that targeted-therapy approaches would be better adapted for these patients, while MHI can be managed with classic therapies.

Cytomegalovirus chronic retinal necrosis with ganciclovir resistance: a case report.

Cytomegalovirus (CMV) chronic retinal necrosis (CRN) is a rare viral retinal infection that occurs in mildly immunocompromised people. It shares some features with both acute retinal necrosis and CMV retinitis. It is typically treated with combination intravitreal and systemic ganciclovir. We discuss the management of a case of CMV CRN with ganciclovir resistance. An 80-year-old female presented with one month of blurry vision in the left eye. She was being treated with abatacept, methotrexate, and prednisone for rheumatoid arthritis. Examination revealed anterior chamber and vitreous cell along with peripheral retinal whitening. Fluorescein angiogram showed diffuse retinal non-perfusion. Aqueous fluid PCR testing returned positive for CMV. The retinitis was initially controlled with oral and intravitreal ganciclovir, but then recurred and progressed despite these therapies. Ganciclovir resistance was suspected and the patient was switched to intravitreal foscarnet injections, along with oral letermovir and leflunomide, which lead to resolution of the retinitis. The patient has now continued with letermovir and leflunomide for approximately 2.5 years without reactivation of the retinitis or need for further intravitreal anti-viral injections and with adequate control of her rheumatoid arthritis. The incidence of CMV CRN may increase in the future as the use of non-cytotoxic immunosuppressive therapies that result in relatively mild immunosuppression also increases. Treatment with ganciclovir is effective but frequently leads to resistance, as in our case. In this situation, combination therapy with letermovir and leflunomide, particularly in the setting of rheumatoid arthritis where leflunomide can also have an anti-inflammatory effect, can be considered.

Clinical characteristics and outcomes of overt gastrointestinal bleeding in children undergoing haploidentical hematopoietic stem cell transplantation: a single-center retrospective analysis

BackgroundOvert gastrointestinal bleeding (GIB) is a potentially serious and life-threatening condition in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, relatively little information is available regarding overt GIB in children.ObjectivesTo assess the prevalence, clinical patterns, and outcomes of overt GIB in children undergoing haploidentical hematopoietic stem cell transplantation (haplo-HSCT).MethodsA total of 123 consecutive patients with malignant or non-malignant blood disorders who received haplo-HSCT were reviewed in our hospital between October 2017 and October 2022. Overt GIB was determined as hematemesis, melena or hematochezia. Continuous variables were compared by Mann Whitney U test. Categorical parameters were compared by the χ2 test or Fisher’s exact test. Kaplan-Meier curves and log-rank tests were used to assess overall survival (OS), non-relapse mortality (NRM) and relapse. Univariate and multivariate analyses were performed to identify potential risk factors of overt GIB development.ResultsThe median follow-up was 26.3 (range,1.7–74.8) months. Overt GIB occurred in 31 patients (25.2% incidence), with a median time elapsed after haplo-HSCT of 376 days (range, 58–1275 days). Compared with the non-GIB group, patients with overt GIB had reduced OS and increased NRM. In multivariate analysis, grade III–IV gut acute graft versus-host disease (aGvHD), thrombotic microangiopathy (TMA) and cytomegalovirus (CMV) viremia were significant risk factors for the occurrence of overt GIB after haplo-HSCT.ConclusionsOvert GIB is a frequent complication after haplo-HSCT in pediatric patients, and associated with worse survival. Grade III–IV gut aGvHD, TMA and CMV viremia were associated with its development.

Hypomagnesemia May Predict Better Survival and Reduced Nonrelapse Mortality in Allogeneic Hematopoietic Stem Cell Transplantation Recipients

Magnesium (Mg) is an essential element that is required as a cofactor for many cellular reactions, including immunologic pathways. The aim of this study was to investigate the potential impact of serum Mg levels on allogeneic hematopoietic stem cell transplantation (alloHSCT) outcomes. Medical records of 340 alloHSCT recipients (median age: 45 [18-71] years; M/F: 210/130) were reviewed for this retrospective study. Serum Mg levels on days -28, -7, 0, +7, +14, +21, +30, +60, and +90 were included in the analysis. Serum Mg+14 levels predicted nonrelapse mortality (NRM) (P = .025) and had a significant impact on the development of mucositis (P = .027), fungal infection (P = .006), engraftment syndrome (P < .001), sinusoidal obstruction syndrome (SOS) (P = .001), cytomegalovirus (CMV) reactivation (P = .039), and acute graft vs host disease (GvHD) (P < .001). Based on the optimal threshold of serum Mg+14 level (1.33 mg/dL; area under the curve: 0.581 [0.515-0.648]; P = .018), the study group was divided into 2 subgroups as low- and high-Mg+14. The incidence of acute GvHD (P = .002), SOS (P = .013), engraftment syndrome (P = .013), CMV reactivation (P = .001), and Epstein Barr virus reactivation (P = .005) was significantly lower in low-Mg+14 group. The probability of overall survival (OS) was significantly better (P = .002), whereas NRM was lower in the low-Mg+14 group (P = .001). Hypomagnesemia seems to provide a considerable advantage for the post-transplant outcome, which may confirm its potential role in the immunologic microenvironment and adaptive immunity.

Review Article] Cytomegalovirus Infection

Cytomegalovirus (CMV) is a common viral pathogen. Most people who have acute CMV will have an undetectable infection. It is known that cytomegalovirus (CMV) is the most prevalent congenital viral infection in individuals and a significant factor in morbidity and mortality in immunosuppressed hosts, as well as a significant factor in neurodevelopmental disabilities and sensorineural hearing loss. In order to screen for congenital CMV infection, PCR assays are currently being evaluated.

Multiple Immune and Genetic Mechanisms Contribute to Cmv5s-Driven Susceptibility and Tissue Damage during Acute Murine Cytomegalovirus Infection.

The MHC class I molecule H-2Dk conveys resistance to acute murine CMV infection in both C57L (H-2Dk transgenic) and MA/My mice. M.H2k/b mice are on an MA/My background aside from a C57L-derived region spanning the MHC (Cmv5s), which diminishes this resistance and causes significant spleen histopathology. To hone in on the effector elements within the Cmv5s interval, we generated several Cmv5-recombinant congenic mouse strains and screened them invivo, allowing us to narrow the phenotype-associated interval >6-fold and segment the genetic mechanism to at least two independent loci within the MHC region. In addition, we sought to further characterize the Cmv5s-associated phenotypes in their temporal appearance and potential direct relationship to viral load. To this end, we found that Cmv5s histopathology and NK cell activation could not be fully mirrored in the MA/My mice with increased viral dose, and that marginal zone destruction was the first apparent Cmv5s phenotype, being reliably quantified as early as 2 d postinfection in the M.H2k/b mice, prior to divergence in viral load, weight loss, or NK cell phenotype. Finally, we further dissect NK cell involvement, finding no intrinsic differences in NK cell function, despite increased upregulation of activation markers and checkpoint receptors. In conclusion, these data dissect the genetic and immunologic underpinnings of Cmv5 and reveal a model in which polymorphism within the MHC region of the genome leads to the development of tissue damage and corrupts protective NK cell immunity during acute viral infection.

Immunological features of acute cytomegalovirus infection in immunocompetent patients

Objective. To identify and evaluate immunological features in immunocompetent patients with acute cytomegalovirus infection (CMVI).Materials and methods. Thirty-three immunocompetent adult patients with acute cytomegalovirus infection were included in the study; 4 of them had thrombotic complications. The control group consisted of 10 healthy donors. All 33 blood samples were tested by flow cytometry. The content of antigen-specific cells was checked in all patients. Results. All patients had positive cytomegalovirus DNA PCR tests. The content of activated T cells in patients with acute CMV infection and thrombotic complications is 7.7 times higher (p &lt; 0.001) than in conditionally healthy patients (median values: 36.02% (31.01; 47.92) and 4.68% (3.39; 5.25), respectively). The content of granulocytic myeloid suppressor cells (G-MLSC) in patients with acute CMV infection and thrombosis exceeds the same indicator in the group of healthy volunteers by 8.3 times (p &lt; 0.001) (median values were 0.38% (0.24; 0.54) and 0.05% (0.03; 0.07) respectively). The number of regulatory T cells in patients with acute CMV infection and thrombosis was reduced by 3.1 times (p &lt; 0.001) compared to the same indicator in the group of healthy volunteers (median indicators: 0.79% (0.57; 1.09) and 2.45% (2.01; 3.86), respectively). Immunophenotyping of CD3+ cells showed a tendency to increase the proportion of more mature cells, namely effector memory cells (TEM) and terminally differentiated memory cells (TEM RA) with a decrease in the percentage of “naive” cells.Conclusion. A high level of antigen-specific T-cell response and a low content of T-regulatory cells may indicate insufficient control of the proliferation of T-cytotoxic lymphocytes, which may contribute to the long-term persistence of the virus and the development of chronic inflammation of the vessel wall, which requires further study. Thus, in patients with acute CMV infection, an additional risk factor for thrombosis appears, which must be taken into account when carrying out therapeutic and diagnostic measures.

КЛИНИЧЕСКИЕ ОСОБЕННОСТИ ОСТРОЙ ЦИТОМЕГАЛОВИРУСНОЙ ИНФЕКЦИИ, СОПРОВОЖДАЮЩЕЙСЯ ТРОМБОТИЧЕСКИМИ ОСЛОЖНЕНИЯМИ, У ИММУНОКОМПЕТЕНТНЫХ ПАЦИЕНТОВ

Objective of the study. To identify and analyse clinical and laboratory features in immunocompetent patients with thrombotic complications in acute cytomegalovirus infection. Development of the algorithm of prognosis and early diagnosis of thrombotic complications in order to reduce the risk of severe course of the disease and lethal outcome. Materials and Methods. The study included 100 immunocompetent adult patients undergoing inpatient observation and treatment with laboratory-proven acute cytomegalovirus infection. All patients had a detailed clinical and epidemiological history for the possible presence of modifiable and/or non-modifiable prothrombotic risk factors; a multifaceted laboratory and instrumental examination was performed. Results. Out of one hundred patients with acute cytomegalovirus infection selected in the study, thrombotic diseases were observed in 7% of cases (in 7 patients). The mean age of the patients was 41 (38; 42) years. Patients were hospitalised on average on 12 (10; 14) days from the onset of the disease. The main complaints on admission were: prolonged fever up to 38°C and marked general weakness. The patients had elevated ALT and AST in 88% and 80% of cases, respectively. The presence of reactive lymphocytes was registered in 57% of cases. Enlargement of liver and spleen was observed in 67% and 70% of cases, respectively. Compared to patients with uncomplicated course of acute cytomegalovirus infection, statistically significant laboratory differences were observed in SRB (p&lt;0.001) and D-dimers (p&lt;0.05) in patients who had thrombotic complications. All patients who had genetic material (DNA) to CMV in the blood had positive tests for rr65 antigenemia. The polymorphism of factor V gene G1691A (FVLeiden) was detected in only one patient, who was a carrier of heterozygous GA allele. Conclusion. Acute cytomegalovirus infection in immunocompetent patients includes a symptom complex consisting of a typical clinical picture (prolonged febrile intoxication, hepatosplenomegaly, elevated hepatic transaminases, CRP and D-dimer levels) and obligatory laboratory detection of the virus (positive PCR and/or Ag pp65 tests for CMV). Cytomegalovirus is an independent and reliable prothrombotic risk factor, with thrombotic complications occurring in 7% of cases. Patients with risk factors for thrombotic complications with verified acute cytomegalovirus infection are recommended to be prescribed anticoagulant therapy at prophylactic doses. Also, patients with a proven case of thrombotic process on the background of acute cytomegalovirus infection are recommended a course of etiotropic antiviral therapy.

Acute Cytomegalovirus infection complicated with Haematophagocytic Lymphohistiocytosis in a young male with an inaugural diagnosis of Systemic Lupus Erythematosus: A case report

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease due to a diverging immune response resulting in immune-mediated damage to tissues with significant morbidity and mortality. Cytomegalovirus (CMV) is a constantly encountered, widespread herpesvirus with a mild impact on immunocompetent hosts but can lead to significant morbidity and mortality in the immunocompromised host. Hemophagocytic lymphohistiocytosis (HLH) is a rare and potentially fatal clinical condition with a collection of symptoms resulting from exaggerated immune activation, response, and cytokine storm. HLH can be primary which is genetically predisposed, and secondary which is usually preceded by an infection or an inflammatory process which then is referred to as macrophage activation syndrome. Here we report a rare case of a young male with an inaugural diagnosis of SLE complicated with HLH following a recent CMV infection.

Review Article] Cytomegalovirus Infection

Cytomegalovirus (CMV) is a common viral pathogen. Most people who have acute CMV will have an undetectable infection. It is known that cytomegalovirus (CMV) is the most prevalent congenital viral infection in individuals and a significant factor in morbidity and mortality in immunosuppressed hosts, as well as a significant factor in neurodevelopmental disabilities and sensorineural hearing loss. In order to screen for congenital CMV infection, PCR assays are currently being evaluated.

Acute cytomegalovirus proctitis and epididymitis acquired via sexual transmission in an immunocompetent patient: a case report

BackgroundWe present a case report of an immunocompetent host with presumed sexually transmitted cytomegalovirus proctitis and epididymitis, where there currently is a sparsity of published data.Case presentationA 21-year-old previously healthy Caucasian individual was admitted for severe rectal and testicular pain in the setting of proctitis and epididymitis. Serology and rectal pathology confirmed acute primary cytomegalovirus infection.ConclusionsThis report details his diagnostic workup and highlights cytomegalovirus as a rare cause of sexually transmitted disease among immunocompetent persons.

Cytomegalovirus Infection-related Immune Thrombocytopenia: A Case Report

Immune thrombocytopenia (ITP) is an acquired cause of thrombocytopenia characterized by the presence of autoantibodies against platelets. It may be primary or secondary to several conditions. We present the case of a 63-year-old woman with a diagnosis of immune thrombocytopenia refractory to conventional therapy. After she was tested for secondary causes of ITP, a diagnosis of acute cytomegalovirus (CMV) infection was made. She was treated with ganciclovir and presented normalization of platelet count. CMV-related Immune Thrombocytopenia should always be considered in certain cases of refractory ITP. If the diagnosis of ITP secondary to acute CMV infection is made, specific antiviral therapy with ganciclovir should be considered. In these cases, immunosuppressive agents, such as steroids, may worsen the ITP and should be tapered or withdrawn as rapidly as feasible.

Evaluation of infections in patients with kidney and liver transplantation

Objectives: Infection is a frequent complication of organ transplantation and is associated with significant morbidity and mortality. Methods: Patients who had liver and kidney transplants between 2011 and 2022, who were hospitalized in our hospital, and who were consulted for infectious diseases were retrospectively analyzed from hospital records. Results: Of the patients included in the study, 9 (28%) were female, 23 (72%) were male, and the mean age was 33.7 ± 11.3 years. Patients had congestive heart failure (87.2%, n = 28, hypertension (43.7%, n = 14), and chronic obstructive pulmonary disease (21.8%, n = 7). Twenty (62.5%) kidney transplant recipients and 12 (37.5%) liver transplant recipients were seen within ten years. The most common infections were urinary tract infection in 8 ( 25%) patients and pneumonia in 11 (34.3%). The other infections were gastrointestinal infections such as diarrhoea, bloodstream infections and COVID-19 and Cytomegalovirus. Culture-isolated organisms in 20 (62.5%) of the 32 patients admitted with infections. The microbiological data were notable for some unusual and opportunistic pathogens, including one case of acute cytomegalovirus viremia. Severe sepsis had been seen in six (18.75%) out of 32 patients with documented infections. Conclusions: Infection prevention has become a cornerstone of modern transplantation medicine due to the significant incidence of post-transplant infectious complications resulting from improved immunosuppressive therapies and surgical procedures.

Cytomegalovirus durably primes neutrophil oxidative burst.

Cytomegalovirus (CMV) is a ubiquitous herpes virus that infects most humans, thereafter persisting lifelong in tissues of the host. It is a known pathogen in immunosuppressed patients, but its impact on immunocompetent hosts remains less understood. Recent data have shown that CMV leaves a significant and long-lasting imprint in host immunity that may confer some protection against subsequent bacterial infection. Such innate immune activation may come at a cost, however, with potential to cause immunopathology. Neutrophils are central to many models of immunopathology, and while acute CMV infection is known to influence neutrophil biology, the impact of chronic CMV infection on neutrophil function remains unreported. Using our murine model of CMV infection and latency, we show that chronic CMV causes persistent enhancement of neutrophil oxidative burst well after resolution of acute infection. Moreover, this in vivo priming of marrow neutrophils is associated with enhanced formyl peptide receptor expression, and ultimately constitutive c-Jun N-terminal kinase phosphorylation and enhanced CD14 expression in/on circulating neutrophils. Finally, we show that neutrophil priming is dependent on viral load, suggesting that naturally infected human hosts will show variability in CMV-related neutrophil priming. Altogether, these findings represent a previously unrecognized and potentially important impact of chronic CMV infection on neutrophil responsiveness in immunocompetent hosts.

Acute murine cytomegalovirus infection boosts cell-type specific response and lipid metabolism changes in the liver of infant mice.

Human cytomegalovirus (HCMV) infection in infants can lead to severe diseases, including neonatal hepatitis. The single-cell dimensional changes in immune cells after the initial CMV infection remain elusive, as do the effects of CMV infection on hepatic lipid metabolism. We employed single-cell RNA-sequencing to investigate the changes in liver cell types and immune responses in infant mice following murine CMV (MCMV) infection. Additionally, we examined alterations in protein expression profiles related to lipid metabolism in hepatocytes and the role of the key transcription factor PPAR-γ in hepatocytes during CMV infection. Our study revealed that MCMV infects most liver cell types in infant mice, leading to an increase in the proportion of proliferating CD8 effector T cells and a subset of Nos2+ monocytes, potentially playing an essential role in early anti-viral responses. Furthermore, MCMV infection resulted in altered protein expression of lipid metabolism in hepatocytes. Knocking down the transcription factor PPAR-γ in hepatocytes effectively inhibited CMV infection. Our findings underscore the immune system's response to early-stage MCMV infection and the subsequent impact on hepatic lipid metabolism in infant mice. This research provides new insights into the mechanisms of CMV infection and could pave the way for novel therapeutic strategies.

Fibrinogen Bonn (p. Arg510Cys) in the Aα-Chain Is Associated with High Risk of Venous Thrombosis.

Inherited dysfibrinogenemia is a qualitative defect of fibrinogen caused by various mutations among three fibrinogen genes. Dysfibrinogenemia can be associated with an increased risk of thrombosis, bleeding, or both. Here, we report a 36-year-old female with dysfibrinogenemia who experienced two successful pregnancies under thromboprophylaxis after cerebral venous sinus thrombosis (CVST). In addition to plasmatic coagulation tests, fibrinogen genes FGA, FGB, and FGG were screened using direct genomic DNA sequencing. The structural-functional implications of the detected mutation were analyzed in silico. Inherited dysfibrinogenemia was diagnosed in an index patient after CVST in a risk situation. Anticoagulation with warfarin was stopped after 12 months when the first pregnancy was planned. Pregnancy and spontaneous delivery (2020) was uncomplicated. A second pregnancy was interrupted because of acute cytomegalovirus infection and the third pregnancy was successful in 2022. Pregnancies were accompanied by thromboprophylaxis with enoxaparin 40 mg once daily until 6 weeks postpartum. Substitution of fibrinogen has not become necessary in the index patient so far. Genetic analysis revealed a novel missense mutation (p. Arg510Cys) in the FGA gene ("fibrinogen Bonn") in the index patient, as well as an asymptomatic sister, and their father who experienced recurrent pulmonary embolism. Surface exposure of wild-type Arg510 suggested the mutated Cys510 to form nonnative disulfide bonds with surface-exposed reactive cysteines from other plasma proteins like albumin leading to formation of aggregates and impaired fibrinolysis. Fibrinogen Bonn might be associated with an increased risk of thrombosis, possibly due to impaired polymerization.

Diagnosis of Epstein-Barr and cytomegalovirus infections using decision trees: an effective way to avoid antibiotic overuse in paediatric tonsillopharyngitis

BackgroundThe incidence of tonsillopharyngitis is especially prevalent in children. Despite the fact that viruses cause the majority of infections, antibiotics are frequently used as a treatment, contrary to international guidelines. This is not only an inappropriate method of treatment for viral infections, but it also significantly contributes to the emergence of antibiotic-resistant strains. In this study, EBV and CMV-related tonsillopharyngitis were distinguished from other pathogens by using machine learning techniques to construct a classification tree based on clinical characteristics.Materials and methodsIn 2016 and 2017, we assessed information regarding 242 children with tonsillopharyngitis. Patients were categorized according to whether acute cytomegalovirus or Epstein-Barr virus infections were confirmed (n = 91) or not (n = 151). Based on symptoms and blood test parameters, we constructed decision trees to discriminate the two groups. The classification efficiency of the model was characterized by its sensitivity, specificity, positive predictive value, and negative predictive value. Fisher’s exact and Welch’s tests were used to perform univariable statistical analyses.ResultsThe best decision tree distinguished EBV/CMV infection from non-EBV/CMV group with 83.33% positive predictive value, 88.90% sensitivity and 90.30% specificity. GPT (U/l) was found to be the most discriminatory variable (p < 0.0001). Using the model, unnecessary antibiotic treatment could be reduced by 66.66% (p = 0.0002).DiscussionOur classification model can be used as a diagnostic decision support tool to distinguish EBC/CMV infection from non EBV/CMV tonsillopharyngitis, thereby significantly reducing the overuse of antibiotics. It is hoped that the model may become a tool worth considering in routine clinical practice and may be developed to differentiate between viral and bacterial infections.

#6846 CHRONIC CMV DIARRHOEA IN RENAL TRANPLANT RECIPIENTS - AN UNDERRECOGNISED SPECTRUM OF COMPARTMENTALISED GUT INVASIVE CMV DISEASE

Abstract Background and Aims Chronic diarrhoea in post-renal transplant recipients due to Cytomegalovirus (CMV) presents as Blood CMV PCR (polymerised chain reaction) positive chronic diarrhoea and Gut-invasive (rectal tissue PCR positive, blood PCR-negative) compartmentalised CMV. The available literature on compartmentalised gut CMV is scarce. The aim is to study the clinical presentation and outcome of patients with compartmentalized gut invasive CMV when compared with Blood CMV positive chronic diarrhea in renal transplant recipients. Method This is a retrospective single-centre follow-up study of patients with CMV disease who were transplanted between 2000 and 2020. Diagnostic variables like blood CMV PCR (polymerised chain reaction) positivity with constitutional symptoms, presence or absence of chronic diarrhoea, tissue PCR positivity and site of tissue biopsy were given harmony codes and 6 syndromes were identified – CMV diarrhoea (Blood PCR positive, presence of diarrhoea), compartmentalized gut invasive CMV (Blood PCR negative, presence of diarrhoea, rectal tissue quantitative CMV PCR positive), Acute CMV syndrome, CMV Esophagitis, CMV nephropathy, CMV cystitis. Out of which patients presenting with diarrhoea (first two groups) were included for analysis. The baseline descriptive statistical measures were carried out using analysis of variance. The time to CMV disease from transplant was computed by identifying the pattern of distribution at 10%, 50% and 90% between groups using reliability models. The time to death from diagnosis was analyzed by identifying the pattern by parametric log-logistic distribution. Survival analysis was done by a parametric reliability model identifying location, scale and threshold parameters, from which month-wise prediction of probabilities was found for survival. The proportion of adverse outcomes (relapse, death and graft loss) between the two groups were analyzed by one-way ANOVA and Tukey pairwise comparison. All the patients were followed up till death or last follow-up. Results Out of 2208 renal transplants done between 2000 and 2020, 118 (5.3%), patients developed CMV disease. Chronic diarrhoea was the presentation in 88 (57%), of which 47 had manifestations of CMV diarrhoea, and 41 had compartmentalized gut CMV. Induction agents used (CMV diarrhoea Vs compartmentalized gut CMV) were basiliximab (51% Vs 56%), ATG (27% Vs 17%), Grafalon (0% Vs,2.4%) and no induction (21%,24%). Only 31.9% and 26.8% received Valganciclovir prophylaxis for pre-specified indications respectively. The time to CMV diagnosis from transplant for 10%, 50% and 90% of patients (in months) was 12,63,154 for CMV diarrhoea;12,52 and 139 months for compartmentalized gut CMV. The mean duration (weeks) of diarrhoea was similar in both groups (7 Vs 7.3). Associated opportunistic infections causing diarrhoea were higher in compartmentalized gut CMV (28% Vs 46% p = 0.08); the commonest being cryptosporidium. Quantitative PCR in the blood ranged from 1245 to 2511345 copies/ml; whereas in gut tissue, it ranged from 1325 to 3517920/25 mg. The major histopathological finding in compartmentalized gut CMV was active inflammatory pathology in 34 (83%) patients. The probability of survival was significantly lower (72.6%; CI 60% to 83%) in CMV diarrhoea when compared with compartmentalized Gut CMV (87.2%; CI 76% to 94%) for initial 12 months (p&amp;lt;0.05); however at 5 years (56.2%, Vs 58.5%) and 10 years (48.5% Vs 42.7%) the survival was similar. Compartmentalized gut CMV was associated with a higher relapse rate (19.5%) when compared with CMV diarrhoea (6.4%) on follow-up (p = 0.06). The mortality (36% Vs 29%; p = 0.490) and graft loss (25% Vs 22%; p = 0.692) were similar between both the group. Conclusion Compartmentalized gut invasive CMV represents a larger proportion of chronic diarrhoeal illness with a higher relapse rate, which needs invasive gut tissue PCR analysis, despite negative blood PCR, for early diagnosis and management.

Definition and mapping of Cmv5interval associated effects on the innate immune response to acute Murine Cytomegalovirus infection.

Abstract MHC-I molecule H-2D kconfers resistance to acute murine cytomegalovirus (MCMV) infection in both C57L and MA/My mice. M.H2 k/bmice are MA/My background aside from a C57L-derived region within the MHC (Cmv5), which diminishes this resistance. Thus M.H2 k/bmice lose more weight during infection and present with increased viral load. Additionally, M.H2 k/bmice have fewer, more activated NK cells and significant spleen histopathology measured by decreased white pulp area, loss of marginal zone definition, and increasing red pulp acellularity. To better understand how the Cmv5interval regulates the response to MCMV, we generated several Cmv5recombinant mouse strains and screened them in vivo, allowing us to narrow the phenotype-associated interval as much as 14 times from the original size of 23.08 Mb. In addition, we sought to further characterize the Cmv5-associated phenotypes in their temporal appearance and potential direct relation to viral load. To this end, we found that many Cmv5phenotypes could not be fully mirrored in the MA/My mice with increased viral dose, and that marginal zone disruption was one of the first Cmv5phenotypes to appear, being reliably quantified as early as 2 days post infection (dpi) in the M.H2 k/bmice. This suggests that splenic tissue disruption, occurring prior to increase in weight loss or NK cell activation, may be a primary target of the Cmv5genetic interval and its impact on the response to MCMV. In conclusion, we verified and defined the Cmv5-associated susceptibility to MCMV infection, generated and tested several Cmv5recombinant strains resulting in a substantially reduced interval size, and determined that the full Cmv5phenotype is unlikely to be a direct result of increased viral load. NIH NIAID R01AI50072, Department of Medicine/Nephrology, Center for Immunity Inflammation and Regenerative Medicine, Beirne B Carter Center for Immunology Research.

Regulation of myeloid cells and inflammation marks increased susceptibility in a genetic model of acute viral infection-induced tissue damage.

Abstract M.H2 k/bmice are identical to MA/My parent strain aside from a C57L-derived region within the MHC, which causes these mice to develop significant splenic tissue damage during acute murine cytomegalovirus (MCMV) infection. To understand how MCMV infection leads to the induction of tissue damage, we probed immunological differences between the M.H2 k/band MA/My mice over time. Using tissue imaging and flow cytometry, we observed increased infiltration of neutrophils to the marginal zones of the M.H2 k/bmice aligning with the appearance of necrosis at 2 days post infection (dpi). While TUNEL staining identified increased cell death within these clusters, apoptosis was reduced, suggesting an inflammatory death pathway in the M.H2 k/bneutrophils. In line with this hypothesis, multiplex ELISA identified increased IL-6 and TGF-β in the spleens of M.H2 k/bmice at this time. Intriguingly, depletion of neutrophils prior to infection did not alleviate M.H2 k/bhistopathology or inflammation. Seeing the differential regulation of neutrophils, we assessed the state of other myeloid populations in the spleen during acute MCMV infection. We observed significant loss of marginal zone and red pulp macrophages (MZMs, RPMs) beginning at 2dpi and worsening over time in the M.H2 k/bmice. Further exploration into how the loss of these populations may contribute to tissue damage identified buildup of toxic lipid peroxidation byproduct 4HNE early in the MZMs and progressing through the RPMs alongside the development of histopathology. In conclusion, we have identified increased inflammation, oxidative stress, and macrophage loss in M.H2 k/bspleens during acute MCMV infection that tracks with localization and temporal appearance of histopathology. NIH NIAID R01AI50072, Department of Medicine/Nephrology, Center for Immunity Inflammation and Regenerative Medicine, Beirne B Carter Center for Immunology Research.